The present invention relates to devices for the administration of drugs.
More particularly, the present invention constitutes an improvement in the solution described in the prior Italian Industrial utility model application 15156-B/89 and the corresponding DE-U-9 003 505.
The application in question relates to a device for the administration of drugs, particularly liquids, comprising a double-walled housing which is open at one end and closed at the other by an end wall, in which a needle is fixed and extends substantially the entire length of the housing. The inner jacket of the housing is threaded at least at its open end so as to receive a threaded spigot of a piston applied in the form of a stopper to the open end of a cylindrical container housing the liquid to be administered. The piston has an axial bore closed by a diaphragm which can be pierced by the needle when the spigot of the piston is screwed into the inner jacket. By forming the cylindrical container axially into the said housing it is possible to supply the said liquid product. The entirety is generally like a syringe; it is also possible to envisage the use of this same structure as a device for supplying infusions.
The present invention attempts principly to improve on this prior solution so as to extend its use to the supply of drugs constituted by a liquid and a powder which must be dissolved in the liquid before use. At present the usual method used with drugs of this type provides for a liquid to be drawn up from a phial into a syringe and then for the liquid to be injected into another phial containing the powdered drug and then--after the drug has dissolved--for the solution to be taken up again in a syringe before the injection proper can be effected: a sequence of operations which is rather complicated and must be carried out with extreme care.
According to the present invention, the object is achieved by means of a device for the administration of drugs having the characteristics claimed specifically in the claims which follow.